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Two galaxies aligned in a way where their gravity acts as a compound lens

(phys.org)
268 points wglb | 3 comments | 16 Nov 24 16:48 UTC | HN request time: 0.657s | source
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wglb ◴[16 Nov 24 16:49 UTC] No.42157343[source]▶
This is seriously cool. One lens galaxy is amazing, but two! (Too bad that this is not steerable.)

Underlying paper: https://arxiv.org/abs/2411.04177

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hinkley ◴[16 Nov 24 19:21 UTC] No.42158524[source]▶
It would be cool if we some day had special days of astronomy where every telescope is turned to galactic eclipses the way they once did for solar eclipses.

The sky is huge and we are moving, so surely some would happen in our lifetimes?

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1. ben_w ◴[17 Nov 24 00:31 UTC] No.42160883[source]▶
Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is.

It takes light, the fastest thing that can be, 100,000 years to cross the Milky Way.

The Sagittarius Dwarf Spheroidal Galaxy is currently in the process of being consumed by the Milky Way and is expected to pass through it within the next 100 million years.

So, unless you're even more optimistic about life extension technology than I am, not in our lifetimes, no.

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2. vlovich123 ◴[17 Nov 24 16:47 UTC] No.42165156[source]▶
> It takes light, the fastest thing that can be, 100,000 years to cross the Milky Way.

Relative to us. For the light itself it takes no time.

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3. ben_w ◴[17 Nov 24 17:34 UTC] No.42165490[source]▶
Our own frame of reference is the only one that matters, given the comment I'm replacing to.